Jaccoud's arthropathy in SLE: findings from a Latin American multiethnic population.

OBJECTIVE: To compare the clinical, laboratory and outcome features of SLE patients with and without Jaccoud's arthropathy (JA) from the Grupo Latino Americano De Estudio del Lupus (GLADEL) cohort. METHODS: 1480 patients with SLE [(34 centres, 9 Latin American countries with a recent diagnosis (≤2 years)] constitute the GLADEL cohort. JA was defined as reducible deformity of the metacarpophalangeal axis, without radiographic erosions at any time. Within this cohort, a nested case-control study was carried out. Control was matched for age, gender and centre in a 1:3 proportion. The variables included were: sociodemographic, clinical and immunological features, disease activity, damage and mortality. Comparisons were performed with Wilcoxon and χ2 tests for continuous and categorical variables, respectively. ORs and 95% CIs and Kaplan-Meier survival curve were estimated. RESULTS: Of 1480 patients, 17 (1.1%) JA patients were identified; 16 (94.1%) of them were women, mean age: 31.0 years (SD 12.0). Five (29.4%) patients presented JA at SLE diagnosis and 12 (70.6%) after. The median follow-up time and all disease features were comparable in both groups except for a higher frequency of pneumonitis in the patients with JA [4 (23.5) vs 1 (2.0); p=0.012; (OR: 15.4; 95% CI 1.6 to 149.6)]. The SLE disease activity index, Systemic Lupus International Collaborating Clinics/American College of Rheumatology damage Index and the Kaplan-Meier survival curve were similar in both groups. CONCLUSION: JA may tend to appear early in the course of SLE; it seems not to have an impact on disease activity, damage accrual or in survival.

Genome-Wide Association Study in an Amerindian Ancestry Population Reveals Novel Systemic Lupus Erythematosus Risk Loci and the Role of European Admixture.

OBJECTIVE: Systemic lupus erythematosus (SLE) is a chronic autoimmune disease with a strong genetic component. We undertook the present work to perform the first genome-wide association study on individuals from the Americas who are enriched for Native American heritage. METHODS: We analyzed 3,710 individuals from the US and 4 countries of Latin America who were diagnosed as having SLE, and healthy controls. Samples were genotyped with HumanOmni1 BeadChip. Data on out-of-study controls genotyped with HumanOmni2.5 were also included. Statistical analyses were performed using SNPtest and SNPGWA. Data were adjusted for genomic control and false discovery rate. Imputation was performed using Impute2 and, for classic HLA alleles, HiBag. Odds ratios (ORs) and 95% confidence intervals (95% CIs) were calculated. RESULTS: The IRF5-TNPO3 region showed the strongest association and largest OR for SLE (rs10488631: genomic control-adjusted P [Pgcadj ] = 2.61 × 10(-29), OR 2.12 [95% CI 1.88-2.39]), followed by HLA class II on the DQA2-DQB1 loci (rs9275572: Pgcadj = 1.11 × 10(-16), OR 1.62 [95% CI 1.46-1.80] and rs9271366: Pgcadj = 6.46 × 10(-12), OR 2.06 [95% CI 1.71-2.50]). Other known SLE loci found to be associated in this population were ITGAM, STAT4, TNIP1, NCF2, and IRAK1. We identified a novel locus on 10q24.33 (rs4917385: Pgcadj = 1.39 × 10(-8)) with an expression quantitative trait locus (eQTL) effect (Peqtl = 8.0 × 10(-37) at USMG5/miR1307), and several new suggestive loci. SLE risk loci previously identified in Europeans and Asians were corroborated. Local ancestry estimation showed that the HLA allele risk contribution is of European ancestral origin. Imputation of HLA alleles suggested that autochthonous Native American haplotypes provide protection against development of SLE. CONCLUSION: Our results demonstrate that studying admixed populations provides new insights in the delineation of the genetic architecture that underlies autoimmune and complex diseases.

Antimalarial treatment may have a time-dependent effect on lupus survival: data from a multinational Latin American inception cohort.

OBJECTIVE: To evaluate the beneficial effect of antimalarial treatment on lupus survival in a large, multiethnic, international longitudinal inception cohort. METHODS: Socioeconomic and demographic characteristics, clinical manifestations, classification criteria, laboratory findings, and treatment variables were examined in patients with systemic lupus erythematosus (SLE) from the Grupo Latino Americano de Estudio del Lupus Eritematoso (GLADEL) cohort. The diagnosis of SLE, according to the American College of Rheumatology criteria, was assessed within 2 years of cohort entry. Cause of death was classified as active disease, infection, cardiovascular complications, thrombosis, malignancy, or other cause. Patients were subdivided by antimalarial use, grouped according to those who had received antimalarial drugs for at least 6 consecutive months (user) and those who had received antimalarial drugs for <6 consecutive months or who had never received antimalarial drugs (nonuser). RESULTS: Of the 1,480 patients included in the GLADEL cohort, 1,141 (77%) were considered antimalarial users, with a mean duration of drug exposure of 48.5 months (range 6-98 months). Death occurred in 89 patients (6.0%). A lower mortality rate was observed in antimalarial users compared with nonusers (4.4% versus 11.5%; P< 0.001). Seventy patients (6.1%) had received antimalarial drugs for 6-11 months, 146 (12.8%) for 1-2 years, and 925 (81.1%) for >2 years. Mortality rates among users by duration of antimalarial treatment (per 1,000 person-months of followup) were 3.85 (95% confidence interval [95% CI] 1.41-8.37), 2.7 (95% CI 1.41-4.76), and 0.54 (95% CI 0.37-0.77), respectively, while for nonusers, the mortality rate was 3.07 (95% CI 2.18-4.20) (P for trend < 0.001). After adjustment for potential confounders in a Cox regression model, antimalarial use was associated with a 38% reduction in the mortality rate (hazard ratio 0.62, 95% CI 0.39-0.99). CONCLUSION: Antimalarial drugs were shown to have a protective effect, possibly in a time-dependent manner, on SLE survival. These results suggest that the use of antimalarial treatment should be recommended for patients with lupus.